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Study and evaluation of a frequential multiplexing based on OFDM/OQAM / Etude et évaluation d’un multiplexage fréquentiel basé sur l’OFDM/OQAMGharba, Mohamed 13 July 2012 (has links)
Cette thèse est consacrée à l’étude de la modulation OFDM/OQAM en tant qu’alternative à la modulation OFDM. Nous traitons plus particulièrement le contexte multiusagers. De ce point de vue, les aspects de synchronisation sont déterminants. Les différentes options plus le choix de la forme d’onde sont donc examinés de ce point de vue. Un autre objectif est de montrer de manière précise comment la modulation OFDM/OQAM peut s’adapter à une transmission de type cellulaire, en prenant comme référence le système 3GPP/LTE. Les principales contributions que nous avons apportées sont : 1) Une analyse des phénomènes de désynchronisation : nous analysons l’effet de la désynchronisation, suivant les axes temporel et fréquentiel, sur les performances de l’OFDM/OQAM au récepteur. 2) Méthode de synchronisation : nous analysons une méthode de synchronisation temporelle définie dans un contexte de transmission OFDM/OQAM mono-usager et nous l’adaptons à un scénario de type multi-usagers. 3) Proposition d’un schéma d’accès multiple : nous proposons un schéma d’accès multiple basé sur la modulation OFDM/OQAM, alternatif aux techniques connues OFDMA et SC-FDMA, pour la transmission en liaison montante dans un contexte de type 3GPP/LTE. / This thesis is dedicated to the study of the OFDM/OQAM modulation as an alternative to the OFDM modulation. We treat more especially the multi-user environment. In this respect, synchronization aspects are crucial. The different options plus the choice of the waveform are examined in this point of view. Another objective is to precisely show how the OFDM/OQAM can be adapted to a cellular transmission type, taking as reference the 3GPP/LTE system. The main contributions we have made are : 1) Analysis of the desynchronization phenomena : we analyze the effect of desynchronization, according to the time and frequency axes, on the performance of OFDM/OQAM at the receiver side. 2) Synchronization method : we analyze a method of temporal synchronization defined in a single user OFDM/OQAM transmission and we adapt it to a multi-user scenario type. 3) Proposing for a multiple access scheme : we propose a multiple access scheme based on theOFDM/OQAM modulation, alternative to the known techniques OFDMA and SC-FDMA, for the UL transmission in a 3GPP/LTE context.
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Study and evaluation of a frequential multiplexing based on OFDM/OQAMGharba, Mohamed 13 July 2012 (has links) (PDF)
This thesis is dedicated to the study of the OFDM/OQAM modulation as an alternative to the OFDM modulation. We treat more especially the multi-user environment. In this respect, synchronization aspects are crucial. The different options plus the choice of the waveform are examined in this point of view. Another objective is to precisely show how the OFDM/OQAM can be adapted to a cellular transmission type, taking as reference the 3GPP/LTE system. The main contributions we have made are : 1) Analysis of the desynchronization phenomena : we analyze the effect of desynchronization, according to the time and frequency axes, on the performance of OFDM/OQAM at the receiver side. 2) Synchronization method : we analyze a method of temporal synchronization defined in a single user OFDM/OQAM transmission and we adapt it to a multi-user scenario type. 3) Proposing for a multiple access scheme : we propose a multiple access scheme based on theOFDM/OQAM modulation, alternative to the known techniques OFDMA and SC-FDMA, for the UL transmission in a 3GPP/LTE context.
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